Package boiler



Sept. 18, 1956 J. MARSHALL PACKAGE BOILER 3 SheetsSheet 2 Filed Aug. 5.1953 OO O 4 /l/ //////l o OOOOOOO OOOOOO o OOOO O OOO OOOOO OOOOOOlOIOICIQIOInZ-OIOIOOIOIOIOIOIOIOIOIOIOIOIODOIQIOIOIOlOIOIOIOIOIOlOIOlOIOI P P ooo/ ooo/ ooo/ OOOOOOO OOOOOOO OO OOO OOOOJOIOIOIOIOIOIOIO OOOOOOO INVENTOR.

Leonard J. Marshall Fig. 2.

BY ,fTToRNEY l Sept. 18, 1956 J. MARSHALL 2,763,243

PACKAGE BOILER Filed Aug. 5, 1953 3 Sheets-Sheet 5 Fig. 4.

INI/ENTOR.

Leonard J. Marshall 2,763,243 Patented Sept. 18, 1956 2,763,243 PACKAGEBorLER Leonard J. Marshall, Tenaily, J., assignor to CombustionEngineering, Inc.,l New York, N. Y.,I a corporation of DelawareApplication August s, 195s, serial No. 372,537

1 claim. (ci. 122-347) This invention relates to boilers andparticularly the so-called package boiler which is assembled the boilershop and shipped as an assembled unit the user.

The invention comprises a boiler of the aforementioned type having agenerally elongated horizontal furnace provided with opposed side wallsand opposed front and rear Walls. One of the side walls is composed oftubes which are positioned in side by side relation with adjacent tubesbeing in contact. This wall termina-tes a short distance from the rearwall of the furnace and also forms the side wall of a horizontal gaspass positioned alongside the furnace and which is in communication withthe furnace through the"passage formed betweenv the end of the side Walland rear wall. The opposite ends of the aforementioned side by sidetubes are connected to upper and lower drums, respectively, which extendlongitudinally of the gas pass and are interconnected by a convectiontube bank positioned within the gas pass. Also interconnecting thesedrums are tubes which extend along the roof of the furnace down theother side wall and along or within the bottom of the furnace. The frontand rear walls of the furnace are' similarly linedy with 'tubes andthese latter tubes interconnect the two drums by extending diagonallyfrom the upper and lower ends of the respective front andrear walls to apoin-t immediately adjacent the respective upper and lower drums thenceinto these drums. The furnace is tired -through a suitable opening inthe front wall and the combustion gases generated by the burning of fuelwithin the furnace pass around the rear end of the side wall whichseparates the rfurnace and the gas pass and then flow through the gaspass and into a suitable chimney or stack. Heat generated by thisburning of fuel is absorbed by the various tubes and steam is thusgenerated in the usual manner. l

Package boilers are shipped fromthe boiler factory as assembled unitsand it is therefore necessary that the assemblage be structurally rigidso that when it is being handled and moved about there will be noappreciable relative movement between the elements of the unit sincethis would cause cracking or destruction of the installation andpossible leakage at the connection of the tubes with the drums.'Furthermore, Vin order to insure 'a long life of'this type of boilerwith freedom from maintenance it is desired to provide additional heatabsorption facilities in the locations where high temperature would belikely to burn out tubes. These objectives are realized in the boiler ofthis invention in a unique and highly satisfactory manner.

It is the object of the present invention to provide an improved packageboiler which is extremely rugged and which has its heat absorbing tubesarranged in a most advantageous manner.

Other and further objects of the invention will become apparent to thoseskilled in the art as the description proceeds.

With the aforementioned objects in View, the invention comprises anarrangement, construction and combination of the elements of the boilerin such a manner as to attain the results desired as hereinafter moreparticularly set forth in the following detailed description of anillustrative embodiment, said embodiment being shown by the accompanyingdrawing wherein:

Figure 1 is a vertical section through the boiler looking toward therear thereof and taken generally along line 1--1 of Fig. 2;

Figure 2 is a horizontal section taken generally' along line 2-2 of Fig.1;

Figure 3 is a view similar to that of Fig. 1 but looking toward thefront of the boiler and taken generally along line 3-3 of Fig. 2;

Figure 4 is a fragmentary perspective view showing the interconnectionof a number of tubes with the drums and including the tubes lining therear wall of the furnace.

Referring now to the drawings, wherein like reference charactersdesignate like elements throughout the several views, the package boilershown therein is provided with a furnace 10 which includes front wall12, Arear wall 14 and side walls 16 and 18. Extending alongside furnace10 is gas pass 20 which is separated from the furnace by side wall 18and communicates with the furnace through passage 22 formed between theend of side wall 18 and the rear Wall 14. The other end of the gas passis provided with outlet passage 23 for discharging combustion gasesgenerated in the furnace to a suitable stack after they have traversedthe length of the gas pass. Extending longitudinally of gas pass 20 andpositioned at the top and bottom of the gas pass are upper and lowerdrums 24 and 26, respectively, the upper of which is the conventionalsteam and water drum while the lower is the conventional mud drum. Thesedrums are interconnected by convection tube bank 25 which extendsthroughi outv the length of gas pass 20 for the absorption of heat fromthe combustion gases flowing through the gas pass from passage 22 topassage 23. As embodied the outermost tubes of this tube bank line theouter walls of the gas pass and give support thereto. Alsointerconnecting drums 24 and 26 are tubes 28 which form wall 18 and forthis purpose are arranged in side by side relation with adjacent tubesbeing in contact and welded together.

Extending along side wall 16 of the furnace are tubes 30 which are bentat the upper and lower ends of the side wall so that the upper portionsof the tubes extend along roof 32 and connect into drum 24 while thelower portions are imbedded in floor 34 and connect into drum 26.

The rear wall 14 of furnace 10 is lined with tubes 36 which extendvertically of the wall and are bent at the upper and lower ends of thewall so that they extend diagonally toward their respective upper andlower drums 24 and 26. As best shown in Fig, 4, the diagonal extensionof the upper portions of tubes 36 underlie the portions of tubes 30which extend along roof 32 while the diagonal extension of the lowerportions of tubes 36 overlie the portions of tubes 30 that are imbeddedin floor 34. These diagonal extensions of the tubes 36 extend to a pointimmediately adjacent the respective drums 24 and 26 where they are bentso that as to radially enter the drums.

The front wall 12 is lined with tubes 38 in the same manner tubes 36line rear wall 14 with the diagonal portions of tubes 38 underlying andoverlying the upper and lower portions respectively of tubes 30 in thesame manner as tubes 36, Since furnace 10 is fired through front wall 12which is provided with opening 40 for this purpose, tubes 38 are bentaround this opening in order to accommodate the insertion of a suitableburner thereinto and to permit the unobstructed projection of fuel intothe furnace.

One of the purposes of arranging the upper and lower extended portionsof tubes 38 and 36 diagonally rather than in some other manner is toprovide as rigid a support as possible for the frontL and rear walls,respectively, ofthe furnace towithstandV the effect of lateral forcesacting'agai'nst these walls.

In addition to providing diagonal bracingl for the-rear wall of theyfurnace the diagonal extensions of tubes 3'6 together with the upper andlower portions of tubes 3'()- provide a double layer of heat absorbingtubes at a very high temperature location in the furnace whichv reducesthe temperature at this location and reduces the possibility of burningthe tubes. Since furnace is fired from front wall 12 the hot gases ofcombustion sweep length wiseof the furnace towardrear wall 14 and passthrough the relatively restricted passage 22 adjacent the rear wall andinto gas pass 2i); This has the effect of making the zone of` thefunnace'immediately infront of passage 22 a very high temperature zoneand particularly the upper portion of this zone. Thus by-positioning theupper diagonal portions .of tubes 36V immediately beneathl the upperportions ofl tubes 3i) a double layer of tubes is provided at. thislocation of high temperature thereby increasing the heat absorption andeffectively protecting the tube metal from overheating. Furthermore, byinterconnecting drums 24 and 26 by tubes 36 in this diagonall manner thelength of each of the tubes 36 is the shortest possible therebymaintaining the resistance to flow of each tube at a minimum softhat thecirculation through each tube and accordingly the heat absorbed by eachtube is a maximum all -of which insures the required protection at thishigh temperature zone.

Each of the walls of the boiler, except wall 18 which divides furnace 10and gas pass 20 and forms a common` side wall for each of thesechambers, is lined with suitable thermal insulation and refractorymaterial 42 in engagement with the tubes extending along the innersurface of the particular wall and which is held in place by outer steelcasing 44 with the whole unit being mounted upon structural steelbase46.

By lining the inner surface of the outer walls of the entire boiler withtubes which interconnect drums 24 and 26 and particularly by diagonallybracing the end walls of furnace 10 an extremely rigid structure isformed which will readily withstand the rough handling to which such aunit is necessarily subjected.

While I have illustrated and described a preferred embodiment of mynovel'package boiler it is to be under-- stood that such is merelyillustrative and not restrictive and that variations and modications maybe made therein without departing from the spirit and scope of theinvention. Ith-erefore do not wish to be limited to the precise detailsset forth but desire to avail myself of such changes as fall within-thepurview of my invention.

The tubing arrangement disclosed in this case can conveniently beconsidered as made up of the line of tubes 28, the tube bank 25, thesystem of tubes 30, the system of tubes 36 and the system of tubes 38,the three systems each lining one of the walls of the furnace section.

What I claim is:

A package boiler comprising the combination, with a casing, of an upperdrum extending longitudinally of the casing, a lower drum underlying theupper drum and extendinglongitudinally of the casing and a tubingarrangement connectingA said drums; said casing having the form of anelongated rectangle in horizontal cross section and having a front and arear wall arranged in parallelism, parallel side walls and a oor sectionand a roof section; refractory material forming a lining for said wallsand the roof and oor sections; said tubing arrangement comprising asystem of substantially straight contacting tubes communicating withsaid drums and extending in a straight line from the frontrwall of theboiler and. terminating short of therear wall and dividing theV interiorof the boiler into a furnace section andr a gas pass connected by apassage at the rear end of the boiler; said arrange ment of tubesal'socomprising in addition a bank of coni vection tubes communicating withsaid drums and distributed throughout said gas pass with the outermosttubes of said bank engaging the lining of the gas pass, a first systemof tubes having straight vertically extending spaced-apartV intermediatesections engaging the lining of the outer side wall of the furnacesection, a second system of tubes having intermediate straight,vertically extending parallel spaced apart portions engaging the liningof the rear wall of the furnace-section, and a third system of tubeshaving spaced apart vertically extending intermediate portions engagingthe front wall of the furnace section, said front wall having an openingtherein to permit the introduction of the nozzle of a burnertherethrough and said intermediate portions of the tubes of the thirdsystem being arranged to clear the path of discharge of fuel into thefurnace section; the tubes of the first system having their upperportions extending across the furnace in engagement with the materiallining the roof and having their extremities connected at apredetermined level to said upper druml and their lower end portionsextending through the refractory material forming the oor of thefurnacesection and having their extremities connected at a predetermined levelto the lower drum; the upper portions of the tubes of the second andthird systems forming respectively a rear and a front upper set ofstraight parallel spaced apart extensions running obliquely across theupper portion of the furnace section immediately below the upper endportions of the tubes of the first system and said sets of extensionshaving their extremities connected to the upper drum in short straightlines running respectively from the opposite ends of the drum andterminating short ofthe middle thereof, the lower portions of the tubesof the second and third systems forming respectively a rear and a frontlower set of straight, parallel spaced apart extensions runningdiagonally across the lower part of the furnace section and above theoor thereof, said lower sets of extensions having their extremitiesconnected to the ylower drum in relatively short straight lines runningfrom the opposite ends of the drum toward and stopping short of thecenter thereof at a level above the level of the connection of the lowerportions of thel tubes of the first system to the-lower drum.

References Citedrin the file of this patent UNITED STATES PATENTS

